A communication system is a facility which facilitates communication between two or more entities such as communication devices, network entities and other nodes. A communication system may be provided by one or more interconnect networks and the elements thereof and a plurality of communication devices, for example user devices. One or more gateway nodes may be provided for interconnecting various networks. For example, a gateway node can be provided between an access network and other communication networks. The communication may comprise, for example, communication of data for carrying communications such as voice, electronic mail (email), text message, and multimedia and so on.
A user may communicate via a communication system and access various applications by means of an appropriate communication device. The user communication devices are often referred to as user equipment (UE). An appropriate access system allows the communication device to communicate via the communication system. An access to the communications system may be provided by means of a fixed line or wireless communication interface, or a combination of these. Examples of wireless communication system or network include cellular networks, various wireless local area networks (WLANs), wireless personal area networks (WPANs), and satellite based communication systems and various combinations of these.
In wireless systems a network entity such as a base station provides an access node for communication devices. It is noted that in certain systems, such as the Third Generation (3G) network system like TD-SCDMA (Time Division-Synchronous Code Division Multiple Access), WCDMA (Wideband Code Division Multiple Access) and CDMA (Code Division Multiple Access) 2000, a base station is called ‘Node B’. Typically the operation of a base station node and other apparatus of an access system required for the communication are controlled by an appropriate control entity, such as the Radio Network Controller (RNC). The control entity can be interconnected with other control entities of the communication network.
Actually the 3G networks have been widely deployed in almost all major communication system worldwide. The 3G network requires improvement on its coverage since it does not work well in some scenarios, such as cell edge and high speed moving train.
In TD-SCDMA network, Repeater is suggested to improve the coverage. However, it is obvious that Repeater is not better than relay node which is used in LTE-A (Long Term Evolution-Advanced) technologies. The relay node is used between Node B and a destined node, for example a destined user device to improve the coverage of the Node B.
Two architectures which include four alternatives for the relay node, known as architectures A and B, are provided in documents about LTE-A technologies, such as 3GPP TR36.806. However, because of the difference between LTE-A network and 3G networks, the solutions used in LTE-A will result in some disadvantages if they are directly used in 3G networks.
Accordingly, there is a need for a relay technique which can be used well in 3G networks.